The compression coding and decoding for motion image is generally classified into two prediction technologies for coding and decoding: inter picture coding and decoding as well as intra picture coding and decoding. The technology of intra picture coding/decoding performs predictive coding/decoding on the current coding/decoding image block by using the information from the coded/decoded image block of the current picture. The technology of inter picture coding/decoding performs predictive coding/decoding on the current coding/decoding image by using the information of the picture which has been coded/decoded.
The technology of inter picture coding/decoding provides the inter picture prediction with as small a residue signal as possible for the current picture by performing interpolation filtering on the reference picture. All the interpolation pixels used in the conventional interpolation filter for the reference picture are from the reference picture. However, the image signal after interpolation is used for predicting the current picture, and the image information of the current picture is failed to be used in the conventional interpolation algorithm.
In the proposals on International Video Compression Coding Standard for nearly two years, there is an algorithm for performing second-order prediction on the inter picture prediction information by using the spatially neighboring information of the current coding/decoding unit in the current picture, among the algorithms for improving the inter picture prediction information for coding/decoding. However, during implementation of the present invention, the inventor finds that all of these algorithms are modifications to the inter picture prediction information, and that the video coding and decoding efficiency is not high.